Airplane



July 14, 1925.

G. C. LOENING AIRPLANE 1 B, 31923 .'5 Sheets-Sheet l Filed Nov.

' VENTOR E inv@ 51W: ATTORNEY July 14,1925.

G. C. LOENING AIRPLANE Filed NOV 3 sheets-sheet 2 VENTOR BY ATTORNEYJuly 14, 1925. 1,545,505

I v G. c. LOENING AIRPLANE Filed Nov. a. 1925 5 sheets-sheet s JE/"Lg,3.

/N VEN TUI? /1 TTOHNEV Patented July 14, 1925A. i

UNITED VSTATES PATENT oFFlcE.

GBOVER C. LOENING, OF NEW YORK, N. Y.

AIRPLANE.

Application led November 8, 1923. Serial No. 673,407.

To all whom it may concern:

Be it known that I, GRovER C. LOENING,

a citizen of the United States, and resident of New York city, in thecounty and State cornields, high weeds or other growths, or

l tages both as a on water, and to accomplish this by acombination ofparts in an integral designinvolving practically no loss of weight andhead resistance over ordinary land planes. The plane herein described,illustrated'and claimed is characterized by these features, and by itsrelatively low depth of body and consequent low head resistance, and itslow and centralized disposition of weight and flotation, and by itsability to land without nosing over and without interference with thepropeller. A simple, light, compact,-

and fast-flying airplane, free from the ordinary landing limitations, isthus provided.

The invention resents important advanying-boat and as an amphibianplane. rIhe low center of fin area of flying-boats, ordinarily, due tothe fact that the machine skids at the start of a turn in flight, tendsto unbank the machine. The high center of gravity, resulting from theusual elevated position of the engine, has the same effect, and the twofactors combined make such machines much more ditlicult to handle andmaneuver than land planes. In the plan of construction embraced in myinvention the center of fin area is further lowered in consequence ofthe loweringlof the head-resistance, which would tend to increase theunbanking effect; but I also depress the centerof gravity very greatlyby inverting the engine so as to hang below the propeller shaft which itdrives, this propeller shaft being substantially at the top of a unitaryhead-resistance body, instead of in an elevated position as ordinarily,and thus I cause the center of gravity and the center of lin area to besubstantially coincident or approximate to eachother sothat theireffects are neutralized, and by the same plan I secure small control inthe air than has heretofore been possible.

-The inversion of the engine also results in improved engine operation.

The provlslonv of a retractible landing gear on the body enables themachine to alight on solid land, as well as on water or in snow or mud.A forward nose extension of the lower or boat portion of the body keepsthe machine from nosing over under any landing or alighting conditions,and in the case of a tractor propeller this nose also guards thepropeller from spray or vegetation. Attention may also be called to thefeature of the combination involving the locatlon of the radiator of theengine cooling system at the lower front portion of the body behind thepropeller, where it receives the .propeller draft and effectually coolsthe eng-lne, particularly when taxying for long distances. y s

In the. accompanying drawings illustrat- 1ng the invention: i

Fig. 1 is a side elevation, showin the landing gear in position for aligting thereon;

Fig.y 2 is a front elevation on a larger scale, the outer portions ofthe wings being broken away; and

Fig. 3 is a fro-nt elevation of the body on a still larger scale,showing the landing gear retracted, the upper front portion of the bodyof the enclosure being broken away and the cover omitted.

The central body of the airplane as a whole is designated 1, andcomprises a fuselage with a boat-like lower part 2 havingy ahydroplaning bottom. The lower part preferably has lateral sponsonprojections 3 beyond the side lines of the upper part, making anapparent demarkatiom'which may or may not be constructional. Thevertical members 4, 5, 6, 7 may be considered to be continuous.Functionally, the two parts of the body merge or join as an enclosedheadresistance and low iin-area unit, of which the lower portionis'eXtended as a forwardly projecting nose 8, the top of'which is closedand the bottom of which is in upwardly inclined continuation with theboat bottom.

The rear end of the body founded 4upon its hull portionl carries thetail' or empennage 9 with its rudder 10, horizontal stabilizer 11 andvertical stabilizer 12. With respect to its wings, the machine may bemonoplane, biplane,etc. Upper and lower .supporting surfaces 13 and 14are illustrated supported in an ordinary manner from the central body.Lateral pontoons 15 are carried beneath the lower wings.

The top of the structural upper part of the body, at the front end, isprovided with an engine-bed 16. This bed, it may be noted, has at itsfront end a direct vertical support from the foundation, in the posts 4which rise just within the front of the upper'body portion. The rear endof the bed is supported uppn the posts or bulkhead 5. .An engine 17mounted on the engine bed drives the tractor propeller 18, which standsin front ofthe upper part of the body, clearing the nose 8, by' which itis guarded from beneath. The engine, instead of being erect, is hung byits crank-case flanges 19 on the engine-bed bearers so that its V- rowsof cylinders 20 are contained within the body below the propeller andengine crank shaft 21. Due to this construction, the propeller shaftfinds itself substantially at the top" of a relatively lowhead-resistance body, the furtherhehgght required being merely that of acover 22. A very large saving in head resistance is thus obtained ascompared with overhead or erect mountings of the en ine, and in the caseof an engine like the iberty motor I find that improved engine operationresults from the inversion, owing to the fact that the lubricating oilwhich commonly interferes with the ignition is now shed from thesparking points.

The radiator 23 of the engine-coolingsystem is seen located at the frontof the upper part of the body, below the propeller shaft and the engine,land directly behind the propeller, where it receives the draft from theouter portions of the blades. The radiator is preferably set backslightly froml the front of the enclosure, which at this region containsa regulatable louvre shutter 24. C'onduits 25, 26 are indicated, toplace the radiator in circuit with the water spaces of the engine, butthe details of the cooling` system are not necessary to illustrate'since' such` matters are well understood. The cooling effectsobtainable are very advantageous, particularly when 'taxying for longdistances on water. In this respect, as is well known, flying boats havebeen handicapped, because at such low speeds the cooling has beeninsuflicient to prevent overheating of the engine.

A retractible landin -gear is designated generally 27. The il ustratedgear comprises a pair of wheels 28 mounted rotatably on stubs 29 ontheends of V-strut axle frames 30, which are hinged to brackets 31 onopposite sides of the-lower part of the body, preferably at the outercorners of the sponsons 3, obtaining a wide wheel-base. The two brackets31 of each axle frame are members.

spaced lengthwise of the side of the body, and the hinging permits theframes to be swung from the outward projecting positions f Fig. 2,upward and inward to the retracted positions of Fig. 3, where they lieclose to the upper slopes of the sponsons, the frames being desirablycurved or bent to overhang these portions as shown. In the retractedposition the wheels are partly received in pockets 32 in the top of thehull sponsons, the pockets being tightly walled ofll from the interiorof the hul The landing-gear is operated and yieldingly sustained in thelanding condition by shock-absorbing struts 33, which are pivoted attheir outer ends to horns 34 on the axle frames and at their inner endsto nut travelers 35 operatable byA and along screwsV 36 of self-holdingpitch. The said screws are mounted in diagonal transverse positions inthe hull, their end journal portions supported infixed bearin gs 37, 38,the lowerbearings 37 being adjacent the bottom and the upper bearings 38being at the corners other gears 40 on a transverse operating shaft 41.This shaft is operated by or under the control of the aviator bysuitable connections, for example through a sprocket chain passing froma sprocket wheel 42 on the shaft indicated in Fig. 3.

Each of the struts 33 comprises two relatively slidable, telesco'pedmembers 43, 44, one member being pivoted to the horn 34 and lthe otherto the traveler 35. The inner member 44 carries hooks 45 at oppositesides, projecting through longitudinal slots 46 in the outer member 43,these slots permitting relative longitudinal movement of the two Theouter member 43 likewise bears hooks 47. The -hooks 45 and 47 face awayfrom each other, and are connected by elastics 48. Spring means are thusprovided for yieldingly holding the telescopic strut extended to adegree determined by a stop, here afforded by the abutment of the hooks45 against the ends of the slots 46. When the plane lands the elasticsgive, permitting the strut to shorten under cushioned resistance, thustaking up the shock.

While the preferred and complete embodiment of the invention has beendescribed in detail, I wish it to be understood that I do not limitmyself to the single design illustrated, since part or all of theadvantages of the machine from nosing over from such causes or whenlanding in snow or mush or 4on the water; the small head resistance, on

the other hand, gives greatly increased speed, which results also fromthe comparative lightness of the compact body. The lowering of thecenter of mass due to the invertedposition of the engine, so that thecenter of gravity substantially coincides with the low center of n areaof this type of amphibian plane or flying-boat, gives great ease ofcontrol and maneuverability, heretofore lacking in flying-boat machines.

What I claim as new is:

1. An airplane characterized by the combination of a unitaryhead-.resistance body comprising a boat portion and an enclosed upperportion forming virtually continuous lateral fin area, an engine bed atthe forward upper portion of said body, and an inverted engine supportedon said bed, with its cylinders depending below7 the bed, driving apropeller the shaft of which is substantially at the top of thehead-resistance body, the center of fin area rnd the center of gravityof the body being approximate to each other, whereby decreased headresistance and ease of maneuverability are. secured in a machine of theflying-boat type.

2. An airplane characterized by the com.

bination of a unitary head-resistance body comprising a boat ortion andan enclosed upper portion forming virtually continuous lateral fin area,an engine bed at the forward top portion of said body, and an invertedengine supported on said bed, with its cylinders depending below thebed, directly driving a propeller the shaft of which is substantially atthe top of the head-resistance body, the center of fin area and thecenter of gravity of the body being approximate to each other, wherebydecreased head resistance and ease of maneuverability are securedv in amachine of the flyingboat type. l

3. An airplane characterized by the combination of a unitaryhead-resistance body comprising a boat portion and anenclosed upperportion forming virtually continuous lateral tin area, an engine bed atthe upper portion of said body, and an inverted engine supported on saidbed, with its cylinders depending below the bed, driving a propeller theshaft of which is substantially at the top of the head-resistance body,the center of iin area and the center of gravity of the body beingapproximate to each other, whereby decreased head resistance and ease ofmaneuverability are secured in a machine of the flying-boat type.

4. An airplane characterized. by the combination of a unitaryhead-resistance body comprising a boat portion and an enclosed upperportion forming virtually'continuous lateral fin area, an engine bed atthe forward upper portion of said body, and an ins verted enginesupported on said bed, vwith its cylinders depending below the bed,driving a forward propeller the shaft of which is substantially at thetop of the head-resistance body, the center of fin area and the centerof gravity of the body being approximate to each other, wherebydecreased head resistance and .ease of maneuverability are secured in amachine of the flying-boat type.

5. An airplane characterized by the combination of a unitaryhead-resistance body comprising. a boat portion and an enclosed upperportion forming virtually continuous lateral fin area, the boat portionbeing extended forwardly as a nose, a retractible landing gear on thebody, an engine bed at the forward upper portion of said body, and aninverted engine supported on said bed,

with its cylinders depending below the bed,

driving a propellertheshaft of which is substantially at the top of thehead-resistance body, the center of fin area and the center of gravityof thebody being approximate to each other, whereby decreased headresistance and ease of maneuverability are secured in a machine of theflying-boat type, capable of landing anywhere, on water, land, mud,snow, on in vegetation.

6. An airplane having in combination a unitary head resistance bodycomprising a boat portion and an enclosed upper portion; an engine bedon the upper forward portion of the body, the boat art of the body beingextended as a forwardly projecting nose, an inverted engine supported onsaid engine bed, its cylinders depending below the bed, and a tractorpropeller driven by the engine and guarded by the nose, its shaftsubstantially at the top ofthe body, together with a radiator for theengine cooling system at the front of the body beneath the engine andbehind the propeller.

7. An airplane having in combination a unitary b ead resistance body,the lower part of the body forming a boat' hull and being extended as aforwardly projecting nose, a tractor ropeller guarded by the nose, itsshaft substantially at the top of the body, an engine to drive thepropeller contained in the body, lits cylinders'below the propellershaft, together with a radiator for the engine cooling system at thefront of the body below the propeller shaft and behind the propeller.

GRovER o. LOENING.

